diff options
Diffstat (limited to 'src/devices/cpu/m6502/r65c19.cpp')
-rw-r--r-- | src/devices/cpu/m6502/r65c19.cpp | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/src/devices/cpu/m6502/r65c19.cpp b/src/devices/cpu/m6502/r65c19.cpp new file mode 100644 index 00000000000..9cda9d33a0e --- /dev/null +++ b/src/devices/cpu/m6502/r65c19.cpp @@ -0,0 +1,106 @@ +// license:BSD-3-Clause +// copyright-holders:AJR +/********************************************************************** + + Rockwell R65C19 Microcomputer (MCU) + + TODO: fully describe this MCU and its successors (C29, C39) and + emulate their internal peripherals (only core emulation now) + +**********************************************************************/ + +#include "emu.h" +#include "r65c19.h" +#include "r65c19d.h" + +DEFINE_DEVICE_TYPE(R65C19, r65c19_device, "r65c19", "Rockwell R65C19 MCU") + +r65c19_device::r65c19_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, u32 clock, address_map_constructor internal_map) + : r65c02_device(mconfig, type, tag, owner, clock) + , m_w(0) + , m_i(0) +{ + program_config.m_internal_map = std::move(internal_map); +} + +r65c19_device::r65c19_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) + : r65c19_device(mconfig, R65C19, tag, owner, clock, address_map_constructor()) +{ +} + +std::unique_ptr<util::disasm_interface> r65c19_device::create_disassembler() +{ + return std::make_unique<r65c19_disassembler>(); +} + +void r65c19_device::do_add(u8 v) +{ + P &= ~F_C; + do_adc(v); +} + +u16 r65c19_device::do_accumulate(u16 v, u16 w) +{ + // Compute the sum + s32 result = s16(v) + s16(w); + + // Determine flags and saturate result upon overflow + P &= ~(F_N | F_V); + if (result > 32767) + { + P |= F_V; + result = 32767; + } + else if (result < 0) + { + P |= F_N; + if (result < -32768) + { + P |= F_V; + result = -32768; + } + } + + // MPA and MPY always destroy the old value of Y, as does RND when it overflows + Y = result & 0xff; + + // 16-bit result to W, or high byte to A + return result & 0xffff; +} + +u16 r65c19_device::get_irq_vector() +{ + // TODO: this is a stub + return 0xfffc; +} + +void r65c19_device::device_start() +{ + mintf = std::make_unique<mi_default>(); + + c19_init(); +} + +void r65c19_device::c19_init() +{ + init(); + + state_add(R65C19_W, "W", m_w); + state_add<u8>(R65C19_WL, "WL", + [this]() { return m_w & 0xff; }, + [this](u8 data) { m_w = set_l(m_w, data); }).noshow(); + state_add<u8>(R65C19_WH, "WH", + [this]() { return m_w >> 8; }, + [this](u8 data) { m_w = set_h(m_w, data); }).noshow(); + state_add(R65C19_I, "I", m_i); + + save_item(NAME(m_w)); + save_item(NAME(m_i)); +} + +void r65c19_device::device_reset() +{ + r65c02_device::device_reset(); +} + +#include "cpu/m6502/r65c19.hxx" |